1. Technical Field
This invention relates to a traveling environment recognition device that recognizes a traveling environment of a vehicle.
2. Related Art
Conventionally, various traveling control techniques based on a traveling environment of the vehicle (such as a forward situation of the vehicle), such as Adaptive Cruise Control (ACC) and Pre-Crash Safety (PCS), have been put into practical use. The ACC is adapted to keep an inter-vehicle distance preset by an occupant of one's own vehicle between the own vehicle and a preceding vehicle in front of the own vehicle. The Pre-Crash Safety (PCS) is adapted to increase braking force of one's own vehicle in cases where a probability of collision of the own vehicle with an object located on a traveling course of the own vehicle (such as a preceding vehicle and a guardrail) becomes larger than a prescribed value.
To achieve more accurate vehicle traveling control, it is essential to more accurately recognize the traveling environment of the vehicle. The traveling environment of the vehicle can be detected not only through a camera or a radar device or the like, but also through map data. However, since the traveling environment that can be determined through the map data is less accurate than the actual traveling environment that can be detected in real time through the camera or the radar device, the map data cannot be expected to lead to fully accurate vehicle traveling control.
Japanese Patent Application Publication No. 2008-3253 discloses a road shape acquisition device that can improve accuracy of the map data. This road shape acquisition device generates a gridded link plane associated with a link representing a road on the map, updates a white line existence probability for each grid cell according to a Bayes update expression where the white line is detected by a camera, and acquires an actual road shape from the cells that have a high resultant white line existence probability, which leads to high accuracy of the map data.
However, as described above, since the map data is less accurate than the detection result obtained by the camera or the like, combination of the detection result with the map data (more specifically, the link plane associated with the link) as described in Japanese Patent Application Publication No. 2008-3253 may lead to a large deviation from an actual spatial position.
In consideration of the foregoing, exemplary embodiments of the present invention are directed to providing a traveling environment recognition device that can accurately recognize a traveling environment of a vehicle.